Your comments
No idea about your situation. Can you add any other URL on the app?
Oops, you tried on web browser. My bad.
The URL works on VLC media player on my desktop and XiiaLive Pro on my Android. Can you try pasting the URL and "browse" it on Safari? I've been away from iOS for a century, but I wanna know if the browser could download anything correctly (maybe it's an m3u8 file or the stream itself) or not.
Still there? Where are you now? I am living in Japan, and I confirmed the URL works and listened to it clearly. In such case, you might be in the oustside of Japan. How about it?
Customer support service by UserEcho
1615034117359.xl
I attached a file of my favourite backup where I added NHK with the URL you provided. I cannot instruct how to restore it, and it might wipe your all favourite. But hope restoring works good for you.